Conventionally, as a transmissive type liquid crystal display, transmissive type color liquid crystal displays, which perform color display using a back light, placed on the rear surface or side surface of an electrode substrate positioned at the back surface side, as a light source is widely spread.
On the other hand, recently, liquid crystal displays are expected for use as portable displays such as mobile equipments and the like, taking advantage of features such as low power consumption and weight saving is possible. However, in the transmissive type color liquid crystal displays having a built-in back light as described above, the built-in light source consumes high power. Therefore, there are problems that the usable time of a battery is short and that the apparatus is heavy and bulky since the proportion of a battery in the apparatus is large.
Therefore, a reflective type color liquid crystal display having no built-in back light is put into practical use. Since this reflective type color liquid crystal display has no built-in back light, low power consumption can be realized, the apparatus can be small, light and thin, namely, suitable as a mobile display.
However, since a reflective type color liquid crystal display does not sufficiently function in a dark place of poor outer light. Therefore, although it slightly sacrifices the portable property, a portable liquid crystal display of transmissive type and reflective type combined together is practically extremely useful.
In the above mentioned transmissive type color liquid crystal display, a displaying function decreases remarkably under strong outer light such as outdoor and the like, while in a reflective type color liquid crystal display, utterly oppositely, a displaying function increases. In a place of poor outer light, the reflective type color liquid crystal display does not function at all, while the transmissive type color liquid crystal display manifests further increased visibility in proportion to darkness of peripheral areas.
In view of such circumstances, recently, transflective type liquid crystal displays having a function of the transmissive type color liquid crystal display and a function of the reflective type color liquid crystal display combined together are provided. These displays are suitably used as portable terminals and the like used both under strong outer light such as outdoor and the like and under poor outer light such as indoor and the like (see, Japanese Patent Application Laid-Open (JP-A) No. 2002-341331 and JP-A No. 2002-350824).
Also when displaying with such a transflective type color liquid crystal display, a color filter is necessary likewise. However, in a reflective light region, approached outer light usually passes through a color filter twice, while in a transmissive light region, the light usually passes through a color filter once. Therefore, if the same tone is tried to be obtained by using the same coloring material, it is necessary that the thickness of the color filter in the reflective light region is ½ of the thickness of the color filter in the transmissive light region. And in the reflective light region, it is necessary to form a light scattering layer separately like in conventional reflective type color liquid crystal displays. For the above mentioned reasons, a color filter used in the transflective type color liquid crystal displays requires an extra effort in manufacturing.
For example, there is also a constitution, as a color filter 1 shown in FIG. 12, in which the thickness of a coloring layer is reduced to half by forming one transparent layer 3 in between a substrate 2 and a coloring layer 4 in a reflective light region 5. However, it is difficult to make the thickness constant in the reflective light region 5 provided with the transparent layer and a transmissive light region 6 composed only of the coloring layer. As a result, when the color filter is used to constitute a liquid crystal display, there are problems that a transparent electrode such as ITO formed on the color filter is disconnected or that a gap will not be constant.